Information recording medium, apparatus for recording the same and apparatus for recording the same

ABSTRACT

An information recording medium includes: record information pieces logically independent of each other and constituting a hierarchical structure of hierarchical layers; layer information pieces for specifying one of the hierarchical layer; kind information pieces for indicating kinds of information relating to the record information pieces; a text group including layer related texts and record information related texts successively arranged in a mixed manner; text arrangement information pieces corresponding to the text group and arranged in pair with one of the layer information piece and the kind information piece corresponding to the text, the text arrangement information piece indicating a position of the text within the text group. The layer information pieces are arranged in an order in accordance with the hierarchical structure, and the kind information pieces are arranged in pair with the layer information pieces indicating the layer of the corresponding record information piece so as to specify the logical position of the corresponding record information piece within the hierarchical structure.

This is a continuation of application Ser. No. 08/825,560 filed on Mar.20, 1997 U.S. Pat. No. 5,889,746.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an information recording medium such asan optical disk of a high recording density type, which is capable ofrecording information such as video information, audio information andthe like at a high density, and which is represented by a DVD (DigitalVideo or Versatile Disk). The present invention also relates to arecording apparatus for recording the information onto the informationrecording medium, and a reproducing apparatus for reproducing theinformation from the information recording medium.

2. Description of the Related Art

Conventionally, a so-called LD (Laser Disk) and a so-called CD (CompactDisk) are generalized as optical disks, on which information such asvideo information, audio information and the like is recorded.

On the LD or the like, the video information and the audio informationare recorded together with time information indicating a time at whicheach information is to be reproduced with respect to a reproductionstart position, which each LD or the like has, as a standard position.Thus, other than a general normal reproduction to reproduce the recordedinformation in the order of recording, various special reproductions arepossible, such as a reproduction to extract and listen to an onlydesirable music out of a plurality of recorded musics, a reproduction tolisten to the recorded musics in a random order and so on, in case ofthe CD, for example.

In the application of video CD to a karaoke device, the text information(character information) relating to the recorded video information isrecorded on the video CD, and the text information is displayed on amonitor to notify a user of the contents of the recorded videoinformation and/or related information. In the case of the video CD, aportion on the disc is allotted to text information recording area inwhich the text information is recorded. The text information to berecorded is comprised of plural independent files each corresponding toa country for which the text is described (i.e., the files are preparedfor each language), and each file includes a text relating to the wholecontents of the disc and a plurality of texts relating to respectivepieces of the recorded video information. Each text is applied with anidentification number of itself.

However, according to the recording method of the text informationdescribed above, since the text information are simply recordedsuccessively, it is difficult to rapidly recognize the recordingposition of a certain text information which is desired to be displayed.Therefore, it is required to check the contents of every textinformation one after another to find out the target text in atime-consuming manner.

In addition, since the text itself can be described only for the largestunit of the video information recorded on the disc, it is impossible todescribe the text for further departmentalized information units. Forexample, in the case of the video CD on which plural stories arerecorded, it is not possible to describe a text for each chapter and/orscene of each story, although it is possible to describe a text for eachstory.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide aninformation recording medium on which information can be recorded in ahierarchical structure and on which text information can also berecorded in relation with the recorded information at each hierarchicallayer.

It is another object of the present invention to provide an apparatusfor recording the information including the text information on therecording medium, and an apparatus for reproducing the recordedinformation, which is capable of searching for the text informationquickly.

According to one aspect of the present invention, there is provided aninformation recording medium including: a plurality of recordinformation pieces logically independent of each other and constitutinga hierarchical structure including a plurality of hierarchical layers;layer information pieces for specifying one of the plurality ofhierarchical layers; kind information pieces for indicating kinds ofinformation relating to the record information pieces; a text groupincluding a plurality of layer related texts and record informationrelated texts successively arranged in a mixed manner, the layer relatedtext describing information related to the layer specified by the layerinformation piece, the record information related text describinginformation related to the kind of the information specified by the kindinformation piece; text arrangement information pieces corresponding tothe text group and arranged in pair with one of the layer informationpiece and the kind information piece corresponding to the text, the textarrangement information piece indicating a position of the text withinthe text group, wherein the layer information pieces are arranged in anorder in accordance with the hierarchical structure, and the kindinformation pieces are arranged in pair with the layer informationpieces indicating the layer of the corresponding record informationpiece so as to specify the logical position of the corresponding recordinformation piece within the hierarchical structure.

In accordance with the recording medium thus configured, since the textsare related to the hierarchical structure by the layer informationpieces, the texts can be recorded for each of the plural layers.Further, since the text arrangement information pieces are recorded, thesearch operation using the text may be readily performed.

The medium may further includes a plurality of specific layerinformation pieces indicating recording position of the layerinformation pieces which indicate one or more predetermined specificlayers out of the plurality of hierarchical layers. By this, therecording positions of the layer information pieces indicatingpredetermined layers can be readily obtained by referring to thespecific layer information pieces.

The medium may further includes uppermost layer information piecesindicating recording positions of the layer information pieces whichindicate the highest layer out of the plurality of hierarchical layers.By this, the recording positions of the layer information pieces for theuppermost layer can be readily obtained.

The medium may further include relation information pieces indicating,for predetermined kind information pieces, relations between the recordinformation related texts and logical positions of the recordinformation pieces corresponding to the record information related textswithin the hierarchical structure. By this, a rapid search can beachieved using the kind information pieces.

The medium may be so configured that the layer information pieceindicates only the layers, out of the plurality of layers, includingunits of the record information pieces which a user can arbitrarilydesignates. With this treatment, the search of the texts correspondingto the record information designated by the user may be easy and quick.

The medium may be so configured that the layer information piece isrecorded for a certain record information piece which satisfies thefollowing conditions: (a) on a certain layer within the hierarchicallayers lower than the predetermined specific layers, there exist otherrecord information pieces on the layer which is at a same hierarchicallevel as the certain layer and which is branched from the layer just onelevel higher than the certain layer; and (b) there exists at least onetext with respect to one of the certain record information piece and theother record information pieces and the layers lower than the certainlayer. By this, all the existing layers can be accurately described withminimum number of description of the layer information pieces.

The medium may be so configured that the record information related textincludes a classification mark part indicating a sub-class of therelated information described by the text and a character partindicating the related information. By this, the quick search can beaccomplished using the classification mark part in the recordinformation related text.

According to another aspect of the present invention, there is providedan information reproducing apparatus for reproducing information from aninformation recording medium, including: a designating unit fordesignating the record information piece to be searched, the kind of therelated information corresponding to the record information piece to besearched and a search object text relating to the record informationpiece to be searched; a searching unit for searching for the kindinformation piece corresponding to the kind of the related informationdesignated by the designating unit; a selecting unit for selectingrecord information related texts including the search object text out ofthe record information texts which include the kind information piecesdetected by the searching unit, by using the text arrangementinformation pieces paired with the kind information pieces detected bythe searching unit: obtaining unit for obtaining the logical position inthe hierarchical structure and the related information of the recordinformation piece corresponding to the record information related textselected, by referring to the corresponding layer information piece andother layer information pieces; a display unit for displaying theinformation related to the record information obtained by the obtainingunit; and a reproducing unit for reproducing the record informationpiece designated by the designating unit based on the logical positionobtained by the obtaining unit.

In accordance with the reproducing apparatus thus configured, thesearching unit searches for the kind information piece corresponding tothe kind of the related information designated, and the selecting unitselects a record information related texts including the search objecttext. The obtaining unit obtains the logical position in thehierarchical structure and the related information of the recordinformation piece corresponding to the record information related textselected. The reproducing unit reproduces the record information piecedesignated by the designated unit based on the logical positionobtained.

According to still another aspect of the present invention, there isprovided an information reproducing apparatus for reproducinginformation from an information recording medium, including: adesignating unit for designating the record information piece to besearched and the kind of the related information corresponding to therecord information piece to be searched; a searching unit for searchingfor the record information related text including the kind informationpiece corresponding to the kind of the related information designated bythe designating unit and for a logical position in the hierarchicalstructure of the record information corresponding to the recordinformation related text; a display unit for displaying the recordinformation related texts detected by the searching unit; and areproducing unit for reproducing the record information piece designatedby the designating unit based on the logical position detected by thesearching unit.

In accordance with the reproducing apparatus thus configured, thesearching unit searches for the record information related textincluding the kind information piece corresponding to the kind of therelated information designated and for a logical position in thehierarchical structure of the record information corresponding to therecord information related text. The reproducing unit reproduces therecord information piece designated by the designating unit based on thelogical position detected by the searching unit.

According to still another aspect of the present invention, there isprovided an information reproducing apparatus for reproducinginformation form an information recording medium, including: adesignating unit for designating the record information piece to besearched and the sub-class of the information related to the recordinformation piece to be searched; a searching unit for searching for therecord information related texts including the classification mark partcorresponding to the sub-class designated by the designating unit; anobtaining unit for obtaining the logical position in the hierarchicalstructure of the record information corresponding to the recordinformation related text searched by the searching unit and theinformation related to the record information piece, based on thecorresponding layer information piece and the other layer informationpieces; a display unit for displaying information relating to the recordinformation pieces detected by the searching unit; and a reproducingunit for reproducing the record information piece designated by thedesignating unit based on the logical position obtained by the obtainingunit.

In accordance with the reproducing apparatus thus configured, thesearching unit searches for the record information related textsincluding the classification mark part corresponding to the sub-classdesignated by the designating unit. The obtaining unit obtains thelogical position in the hierarchical structure of the record informationcorresponding to the record information related text searched by thesearching unit and the information related to the record informationpiece, based on the corresponding layer information piece and the otherlayer information pieces. The display unit displays information relatingto the record information pieces detected by the searching unit, and thereproducing unit reproduces the record information piece designated bythe designating unit based on the logical position obtained by theobtaining unit.

According to still another aspect of the present invention, there isprovided an information recording apparatus including: a first producingunit for producing a plurality of record information pieces logicallyindependent of each other; a second producing unit for producing layerinformation pieces indicating one of a plurality of layers constitutinga hierarchical structure and kind information pieces indicating kinds ofinformation related to the record information pieces; a text producingunit for producing layer related texts describing information related tothe layer indicated by the layer information pieces and recordinformation related texts describing information related to the kinds ofthe information indicated by the kind information pieces; a firstarranging unit for arranging the layer related texts and the recordinformation related texts on an information recording mediumsuccessively in a mixed manner to form a text group; a third producingunit for producing text arrangement information pieces indicatingpositions of the texts within the text group; a second arranging unitfor arranging the layer information pieces on the recording medium in anorder in accordance with the hierarchical structure; a third arrangingunit for arranging, on the recording medium, the kind information piecesin pair with the layer information pieces indicating the layer of thecorresponding record information piece so as to specify a logicalposition of the corresponding record information piece within thehierarchical structure; and a fourth arranging unit for arranging thetext arrangement information pieces, on the recording medium, in pairwith one of the layer information piece and the kind information piececorresponding to the texts.

In accordance with the recording apparatus thus configured, the firstarranging unit arranges the layer related texts and the recordinformation related texts on an information recording mediumsuccessively in a mixed manner to form a text group. The secondarranging unit arranges the layer information pieces on the recordingmedium in an order in accordance with the hierarchical structure. Thethird arranging unit arranges, on the recording medium, the kindinformation pieces in pair with the layer information pieces indicatingthe layer of the corresponding record information piece so as to specifya logical position of the corresponding record information piece withinthe hierarchical structure. The fourth arranging unit arranges the textarrangement information pieces, on the recording medium, in pair withone of the layer information piece and the kind information piececorresponding to the texts.

The nature, utility, and further features of this invention will be moreclearly apparent from the following detailed description with respect topreferred embodiments of the invention when read in conjunction with theaccompanying drawings briefly described below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing a physical structure of record informationof a DVD as one embodiment of the present invention;

FIG. 2 is a diagram showing frame pictures constructing a GOP;

FIG. 3 is a diagram showing a logical structure of the recordinformation of the DVD in FIG. 1;

FIG. 4 is a diagram showing a structure of an interleaved unit of theDVD in FIG. 1;

FIG. 5 is a block diagram illustrating a hierarchical structure by whichtext information is described and recorded;

FIG. 6 is a table showing definitions of hierarchy description codes;

FIGS. 7A to 7C are tables showing definitions of application descriptioncodes;

FIG. 8 is a table showing definitions of application description codesrelated to genre;

FIG. 9 is a diagram showing a structure of text information;

FIG. 10 shows an example of description of item codes and item texts;

FIG. 11 is a diagram showing a hierarchical structure configured by thedescription example shown in FIG. 10;

FIG. 12 shows another example of description of item codes and itemtexts;

FIG. 13 is a diagram showing a hierarchical structure configured by thedescription example shown in FIG. 12;

FIG. 14 shows still another example of description of item codes anditem texts;

FIG. 15 is a diagram showing a hierarchical layer structure configuredby the description example shown in FIG. 14;

FIGS. 16A to 16C are tables showing definition of applicationdescription codes which include unique codes;

FIG. 17 shows a search table produced using the unique codes;

FIG. 18 is a block diagram of an information recording apparatus forrecording the DVD in FIG. 1;

FIG. 19 is a block diagram of an information reproducing apparatus forreproducing the DVD in FIG. 1;

FIG. 20 is a flowchart showing a search operation using textinformation;

FIG. 21 is a flowchart showing the song search step in FIG. 20;

FIG. 22 is a flowchart showing a search operation using unique codes;and

FIG. 23 shows an example of description of item text for genre.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the accompanying drawings, embodiments of the presentinvention will be now explained. The following explanations will be donefor the embodiment, in which the present invention is applied to theaforementioned DVD.

In the following embodiments, constitutional elements listed on a righthand side in a following list respectively construct examples ofconstitutional elements of the present invention listed on a left handside in the following list.

Record information piece:

Information unit on volume layer or the lower layers Text arrangementinformation piece: Text head pointer Kind information piece: Applicationdescription code Specific layer information piece:

Text pointer (title address)

Uppermost layer information piece:

Text pointer (volume address)

Object information piece: Search table

(I) Embodiment of Information Recording medium

First of all, a physical structure and a logical structure as well as anoperation of a DVD, as one embodiment of the information recordingmedium to which the present invention is applied, will be explained withreference to FIG. 1.

At first, a record format of video information and audio information onthe DVD (i.e. a physical record format) is explained by use in FIG. 1.

As shown in FIG. 1, a DVD 1 as the present embodiment is provided with alead in area LI at its most inner circumferential portion and a lead outarea LO at its most outer circumferential portion, between which videoinformation and audio information are recorded such that they aredivided into a plurality of VTSs 3, each of which has a unique ID(Identification) number (i.e. VTS#1 to VTS#n). Here, the VTS (VideoTitle Set) 3 is a set (bundle) of titles (each of which is oneproduction or one work which an author or producer intends to offer tothe audience), which are related to each other (e.g., which attribute,such as the number, the specification, the corresponding languages etc.of audio and video streams is the same to each other). More concretely,a plurality of movies which are related to the same movie to each otherbut which language of serifs (lines) are different from each other maybe recorded as different titles respectively, or even in case of thesame movies, the theater version and the special version may be recordedas different titles respectively. Ahead of the area where the VTSs 3 arerecorded, a video manager 2 is recorded as shown in FIG. 1. As theinformation recorded in the video manager 2, for example, informationrelated to the whole video and audio information recorded on the DVD 1,such as a menu for accessing each title, information for preventing anillegal copy, an access table for directly accessing each title and soon, is recorded.

One VTS 3 is recorded such that it is divided into a plurality of VOBs10, each of which has an ID number (VOB ID#1, VOB ID#2, . . . ), andcontrol data 11 disposed ahead of the VOBs 10. Here, a data portionconstructed by a plurality of VOBs 10 is defined as a VOB set (VOBS) asshown in FIG. 1. This VOB set is defined to distinguish the VOB 10,which constructs one portion of the VTS 3 as the substantial portion ofthe video and audio information, from the control data 11, whichconstructs another portion of the VTS 3.

In the control data 11 recorded at the head of the VTS 3, informationsuch as PGCI (ProGram Chain Information), which is various informationrelated to a program chain as a logical division obtained by combining aplurality of cells (the "cell" will be described later in detail), isrecorded. In each VOB 10, the substantial portion of the video and audioinformation (i.e. the video and audio information itself other thancontrol information) besides the control information are recorded.

Further, one VOB 10 is constructed of a plurality of cells 20, each ofwhich has an ID number (cell ID#1, cell ID#2, . . . ). Here, one VOB 10is constructed such that it is completed by the plurality of cells 20and that one cell 20 does not strides over two VOBs 10.

Nextly, one cell 20 is constructed of a plurality of VOB units (VOBUs)30, each of which has an ID number (VOBU#1, VOBU#2, . . . ). Here, theVOB unit 30 is an information unit, each of which includes the videoinformation, the audio information and sub picture information (which isdefined as information of a sub picture such as a subtitle of a movieetc.).

One VOB unit 30 is provided with: a navi-pack (a navigation pack) 41 forthe control information; a video pack 42 for the video information; anaudio pack 43 for the audio information; and a sub picture pack 44 forthe sub picture information. Here, in the video pack 42, a packetincluding the video data is recorded. In the audio pack 43, a packetincluding the audio data is recorded. Further, in the sub picture pack44, a packet including graphics such as a character and a diagram as thesub picture, is recorded. In the video packs 42, which data amount isrelatively large as shown in FIG. 1, one or a plurality of GOPs arerecorded within one VOB unit 30. The audio pack 43 and the sub picturepack 44 are disposed intermittently between the video packs 42. It isprescribed by a standard specification of the DVD that there are 8 kindsof audio recordable on the DVD 1 while 32 kinds of sub picturerecordable on the DVD 1.

Further, the video packs 42, the audio packs 43 and the sub picturepacks 44 are recorded such that the reproduction time for one VOBU 30(i.e., the reproduction time corresponding to data recorded between anavi-pack 41 and the next navi-pack 41 neighboring thereto) is equal toor longer than 0.4 second.

Further, there always exists the navi-pack 41 in one VOBU 30. On theother hand, there may not exist each of the video pack 42, the audiopack 43 and the sub picture pack 44 in one VOBU 30, or, even in casethat these packs exist in one VOBU 30, the number of the packs and theorder of the packs are freely determined.

Finally, the navi-pack 41 is provided with: a DSI (Data SearchInformation) packet 51 including search information to search a videoimage or an audio sound desired to be displayed or sound-outputted(concretely, search information such as an address, where the video oraudio to be displayed or sound-outputted is recorded, on the DVD 1); anda PCI (Presentation Control Information) packet 50 including informationrelated to a display control at a time of displaying the video image oroutputting the audio sound, which is searched on the basis of theinformation of the DSI packet 51. Further, all video data included inone VOBU 30 consist of at least one GOP (Group Of Pictures). In the PCIpacket 50, high light information, which defines a display or operationat a time when one selection item is selected out of selection items bythe audience, is included. By the high light information, for example,the change of the picture plane display as well as the display positionto be changed with respect to the selection item selected on a specialpicture plane of selection items (i.e. a so-called menu picture plane)for the audience to select, and the command corresponding to theselected item (i.e. a command to be performed in correspondence with theselected item) are set.

The video information to construct and display a frame, a selectionbutton and the like, which is required to construct and display the menupicture plane, is recorded in the sub picture pack 44 as the sub pictureinformation.

Further, the above described GOP is a minimum picture unit, which can beindependently reproduced and which is determined by a standard based onthe MPEG (Moving Picture Experts Group) 2 method. The MPEG 2 method is apicture compression method adopted at a time of recording the videoinformation onto the DVD 1 in the present embodiment.

Here, the outline of the MPEG 2 method is explained. Namely, in general,frame pictures forward and backward of one frame picture in continuousframe pictures are often resembled to each other and have mutualrelationships. The MPEG 2 method is a method, which is proposed bypaying an attention to this fact, and which generates one frame pictureexisting between a plurality of frame pictures on the basis of theplurality of frame pictures transferred while they are timely separatedby a few or several frames from each other, by means of an interpolatingcalculation based on moving vectors etc. of the original picture. Inthis case, if this one frame picture is to be recorded, it is enough tojust record the information as for a differential vector and a movingvector thereof with respect to the plurality of frame pictures, so as toreproduce this one frame picture by estimating it from the plurality offrame pictures with referring to these vectors, at a time ofreproduction. By this, the compression recording is enabled with respectto the picture.

Further, the scheme of the above explained GOP is explained withreference to FIG. 2. FIG. 2 shows an example of a plurality of framepictures constituting one GOP. In FIG. 2, a case where one GOP 52consists of 12 frame pictures is illustrated (in the MPEG 2 method, thenumber of the frame pictures included in one GOP 52 is not fixed), forexample. Among those frame pictures, a frame picture indicated by areference sign "I" is called as an I picture (Intra-coded picture),which is defined as a frame picture able to be reproduced as a completeframe picture by use of its own picture information. A frame pictureindicated by a reference sign "P" is called as a P picture(Predictive-coded picture), which is defined as a frame picturepredicted or generated by decoding a difference from a predictivepicture compensated and reproduced on the basis of the already decoded Ipicture or other picture. A frame picture indicated by a reference sign"B" is called as a B picture (Bidirectionally Predictive-coded picture),which is defined as a frame picture predicted or reproduced by use ofnot only the already decoded I picture or P picture but also the Ipicture or P picture which is recorded on the optical disk timely in thefuture relative to the pertinent B picture. In FIG. 2, the relationshipin the prediction (i.e. the relationship in the compensation) betweenthe respective pictures are indicated by arrows.

The MPEG 2 method used in the DVD 1 of the present embodiment employs avariable rate method, in which the data amount included in each GOP isnot constant. Namely, in case that the respective pictures included inone GOP 52 correspond to a moving picture, which moving speed is ratherfast and that the mutual relationship between the respective pictures isrelatively small, the data amount constituting the respective picturesis increased, so that the data amount included in one GOP 52 is alsoincreased. On the other hand, in case that the respective picturesincluded in one GOP 52 correspond to a moving picture which moving speedis rather slow and that the mutual relationship between the respectivepictures is relatively large, the data amount constituting therespective pictures is decreased, so that the data amount included inone GOP 52 is also decreased.

In the above explained record format having a hierarchical structure asshown in FIG. 1, each division can be freely set according to theauthor's intention, so as to perform recording on the basis of these setdivisions. By performing the reproduction on the basis of a laterdescribed logical structure for each of these divisions, the variegatedreproduction can be performed.

Neatly, a logical format (logical structure) constructed by combiningthe information recording by the physical divisions shown in FIG. 1 isexplained with reference to FIG. 3. The information is not actuallyrecorded on the DVD 1 in the logical structure of FIG. 3. Instead,information (e.g. access information or time information) to reproduceeach data shown in FIG. 1 by combining them (especially combining thecells 20) in the logical structure shown in FIG. 3, is recorded on theDVD 1, especially in the control data 11.

To make the explanation clear, the following explanation is made fromthe lower hierarchical layer in FIG. 3. One program 60 is logicallyconstructed on the basis of the author's intention by selecting andcombining a plurality of cells 20 among the physical structuresexplained by use of FIG. 1. The program 60 is also a minimum logicalunit, which division can be identified by a system controller of areproducing apparatus described later and which can be accessed by useof a command by the system controller. It is also possible for theauthor to define a gathering of one or more programs 60 as a minimumunit, which can be freely selected to be watched or listened to by theaudience and which is referred to as a PTT (ParT Of Title).

Since one program 60 is logically constructed by selecting a pluralityof cells 20, it is possible to use one cell commonly for a plurality ofprograms 60, namely to perform a so-called "alternative usage" of thecell 20 in which one cell 20 is reproduced in a plurality of differentprograms 60.

Here, as for the number of each cell 20, at a time of treating the cell20 on the physical format shown in FIG. 1, the number is treated as thecell ID number (which is indicated by cell ID # in FIG. 1). On the otherhand, at a time of treating the cell 20 on the logical format shown inFIG. 3, the number is treated as the cell number in the order ofdescription in the PGCI described later.

Next, by combining a plurality of programs 60, one PGC (Program Chain)61 is logically constructed on the basis of the author's intention. Theaforementioned PGCI (ProGram Chain Information) is defined by a unit ofthe PGC 61. The PGCI includes information indicating: the reproductionorder for each program 60 at a time of reproducing each program 60 (bythis reproduction order, a unique program order (#1, #2, . . .) isassigned to each program 60); the reproduction order for each cell 20(by this reproduction order, a unique cell number is assigned to eachcell 20); an address which is a record position of each cell 20 on theDVD 1; the number of the cell 20 positioned at the head of one program60 to be firstly reproduced; a reproduction method for each program 60;and various commands (e.g. commands able to be specified by the authorfor each PGC 61 or each cell 20). The recording position of the PGCI onthe DVD 1 may be in the control data 11 as aforementioned, or in acontrol data (not illustrated) in the video manager 2 if the pertinentPGCI is related to the menu in the video manager 2 (refer to FIG. 1).

In one PGC 61, the substantial video and audio data etc. are included asa combination of the programs 60 (in other words, the combination of thecells 20) other than the above mentioned PGCI.

Further, in one PGC 61, it is possible to perform the alternative usageof the cell 20 as explained before in the explanation for the program 60(i.e. such a usage that the same cell 20 is commonly used by a pluralityof different PGC 61). As the method of reproducing the cell 20 to beused, the author can select a method of reproducing the cells 20 in anorder regardless of the recording order on the DVD 1 (i.e. the method ofreproducing the cells discontinuously arranged, for example, the methodof reproducing the cell 20 prior which is recorded posterior on therecord track) other than a method of reproducing the cell 20 in therecording order on the record track on the DVD 1 as it is (i.e. themethod of reproducing the cells continuously arranged).

Then, one title 62 is logically constructed of one or a plurality ofPGCs 61 (PGC #1, PGC #2, . . .) as shown in FIG. 3. The title 62 is, forexample, a unit corresponding to one movie, and is completed informationwhich the author would like to offer to the audience of the DVD 1.

Finally, one VTS 63 is logically constructed of one or a plurality oftitles 62 (title #1, #2, . . .) as shown in FIG. 3. The title 62included in the VTS 63 has the attributes common to each other. Forexample, the movies based on one movie but in different languagescorrespond to the respective titles 62. The information included in oneVTS 63 shown in FIG. 3 corresponds to information included in one VTS 3shown in FIG. 1. Namely, all information included in the logical VTS 63shown in FIG. 3 is recorded as one VTS 3 in the DVD 1 shown in FIG. 1.

As the author specifies the information divided in the physicalstructure on the DVD 1 on the basis of the above described logicalformat, the video image (e.g. the movie image) for the audience to watchis to be formed.

In the explanations for the physical structure shown in FIG. 1, for theeasy understanding of the content, it has been explained such that aplurality of cells 20 are recorded in the order of the ID numbers.However, in the DVD 1 of the present embodiment, one cell 20 may bedivided into a plurality of interleaved units IU to be actually recordedon the DVD 1, as shown in FIG. 4.

Namely, as shown in FIG. 4, it is assumed that the author constructs onePGC 61A of the cells 20 having the ID numbers 1, 2 and 4, and constructsanother PGC 61B of the cells 20 having the ID number 1, 3 and 4. In thiscase, at a time of reproducing the information from the DVD 1 on thebasis of the PGC 61A, only the cells having the ID number 1, 2, and 4are reproduced, while, at a time or reproducing the information from theDVD 1 on the basis of the PGC 61B, only the cells 20 having the IDnumbers 1, 3 and 4 are reproduced. In the case of the PGC 61A forexample, if the cells 20 are recorded spaced from each other for each IDnumber, a certain time period to jump the optical pickup from the recordposition of the cell 20 having the ID number 2 on the DVD 1 to therecord position of the cell 20 having the ID number 4 on the DVD 1 isrequired in the reproduction. This results in that the continuousreproduction (hereinafter, it is referred to as a "seamlessreproduction") of the cell 20 having the ID number 2 and the cell 20having the ID number 4 may not be possible depending on a capacity of atrack buffer of the reproducing apparatus described later.

Therefore, in the case shown in FIG. 4, the cell 20 having the ID number2 and the cell having the ID number 3 are divided into interleaved unitsIU and are recorded by the interleaved units IU, each having a length,which does not destroy the continuity of an output signal of the trackbuffer even if an input signal to the track buffer is temporarilystopped, in correspondence with an input and output processing speeds atthe track buffer (i.e. the interleaved units IU, each having a lengthwhich allows the track buffer to continuously output the output signaleven if the input signal to the track buffer is ceased while the opticalpickup jumps for the interval of one interleaved unit IU). For example,in case of reproduction based on the PGC 61A, only the interleaved unitsIU constructing the cell 20 corresponding to the ID number 2 arecontinuously detected to be reproduced. In the same manner, in case ofreproduction based on the PGC 61B, only the interleaved units IUconstructing the cell 20 corresponding to the ID number 3 arecontinuously detected to be reproduced. The length of the interleavedunit IU may be determined with considering the capability of a drivingmechanism such as a slider motor to perform the track jump, in additionto the memory capacity of the track buffer.

In this manner, by dividing one cell 20 into a plurality of interleavedunits IU and recording them according to the author's intention, thesignal outputted from the track buffer can be continuous even at a timeof reproducing the PGC 61 including the cells 20 having thediscontinuous ID numbers, so that is possible for the audience to watchcontinuous reproduction video image.

Each interleaved unit IU is completed in one VCB 10, and does not strideover two adjacent VOBs 10. As for the relationship between theinterleaved unit IU and the VOB unit 30, one or a plurality of VOB units30 are included in one interleaved unit IU. One VOB unit 30 is completedin one interleaved unit IU, and is not divided into a plurality ofinterleaved units IU or does not strides over a plurality of interleavedunits IU.

Since it is necessary to record information of various hierarchicallayers, information according to the above-mentioned recording format isquite suitable for the DVD is which, in recording a movie, not only theinformation of the movie itself but also the sounds and/or subtitles,for various languages, of the movie are recorded on a single disk.

Next, the description will be given of a method of additionallyrecording text information (character information) on the DVD on whichthe video information and the audio information are recorded accordingto the above-mentioned physical and logical structures. Here, textinformation is character information relating to the video and audioinformation recorded on the DVD. For example, if a movie program isrecorded on the DVD, the text information includes the characterinformation of the names of the movie, the director, the main actorsand/or actresses and so on, and if a music program is recorded on theDVD, the text information includes the character information of thenames of the songs, the singers, the composers and so on. Theseinformation may be displayed on a monitor, and further may be used forthe menu display and the search operation.

The present invention is characterized in that each text is recorded ina manner being related to the hierarchical structure of the recordedvideo and/or audio information. In this view, first, the descriptionwill be given, with reference to FIG. 5, of the hierarchical structureto which the texts are related when the texts are recorded on the DVD.The physical and logical hierarchical structures of the video and/oraudio information have already been described with reference to FIGS. 1and 3. FIG. 5 shows the hierarchical structure to which the textinformation is related at the time of recording the text information onthe DVD, and the hierarchical structure of the text informationnecessarily becomes, due to the nature of the text information,analogous to the logical structure of the video and/or audio informationshown in FIG. 3. Therefore, it is understood that the text informationis recorded in a manner substantially related to the hierarchicalstructure of the video and/or audio information.

In FIG. 5, the volume shown at the leftmost position is the highest(uppermost) layer, and the cell shown at the rightmost position is thelowest layer. The respective layers will be briefly described below. The"volume" is an information unit which is managed by one video manager 2.The "title" is an information unit which is arbitrarily determined bythe author as described above. The "parental" represents a version ofthe recorded information when information of multiple versions, such asan adult-oriented version and a kids-oriented version for a singlemovie, are recorded. The "parental ID" is an information specifying oneof the multiple versions. The "cell" and "PTT" has already beendescribed.

In the present invention, the text information is recorded in such amanner that the correspondence of the text to the recorded informationis clear. Namely, the text information is recorded so that it is clearas to which information recorded in which layer in the hierarchicalstructure shown in FIG. 5 the text information corresponds. For thispurpose, the concept "item code" is introduced in the present invention.The title code is a code which indicates as to which layer the textcorresponds to or what kind of information (i.e., contents) the textrepresents. The respective texts corresponding to the respective itemcodes are referred to as "item text", respectively. However, it is notedthat there is an item code which has a corresponding item text and hasno corresponding item text. In addition, plural item codes maycorrespond to a single item text. The item codes are classified into twokinds of codes, a hierarchy description code and an applicationdescription code. The hierarchy description code is a code whichindicates as to which layer of the hierarchical structure in FIG. 5 theitem text corresponds. The application description code is a code whichindicates what kind of contents, related to the recorded video and/oraudio information, the item text describes. Namely, the applicationdescription code represents the kind, the attribute and the like ofrecorded information.

FIG. 6 shows the examples of the hierarchy description codes whichconstitute one type of the item codes. As shown, the hierarchydescription codes include the hierarchical codes, main-items codes andsub-item codes. The hierarchical code represents one layer in thehierarchical structure shown in FIG. 5. For example, the hierarchicalcode "0" represents volume, and the hierarchical code "4" representscell. The main-item code and the sub-item code represent informationrelated to the contents of the recorded video and/or audio information,although they are not directly related to the hierarchical structure ofFIG. 5. Therefore, the main-item code and the sub-item code can berecognized as the supplemental layer related to each layer shown in FIG.5. Concretely, the main-item code and the sub-item code include the codeindicating that the information is an angle or an audio or asub-picture, and a code indicating a channel of audio information. Theangle corresponds to an angle of camera taking pictures for videoinformation, and specifies one of the plural angles if the pluralpictures are taken from the plural camera angles on a single time basis(i.e., for the same scene). For the title in which plural angles areprepared, a user can select one of them to be reproduced. Thesub-picture is secondary picture such as lyrics in karaoke songs orsubtitles in a movie. Although a hexadecimal code is assigned to eachitem code in practice, the hierarchy description code is represented asa decimal code in FIG. 6, for the sake of simplicity. The "<RESERVE>"represents a code which is not defined yet, and the "unique code" is acode which the author and/or producer of DVD can arbitrarily define.

FIGS. 7A to 7C show examples of the application description codes whichare one type of the item code. As described above, the applicationdescription code indicates the kind of the contents of the correspondingitem text. Concretely, as shown in FIGS. 7A to 7C, the applicationdescription codes include the series name, production name, the directorof movie, the artist of music, the composer and the like. The contentsrepresented by the application description code is referred to as"application item". The "CLASS" in FIGS. 7A to 7C indicates theclassification of the application items. However, it is provided by theproducer of the text information for the purpose of regulation, andhence it may be omitted. As shown, two kinds of application descriptioncodes, a full-name code and a sorting code, are assigned to eachapplication item. The full-name code is a code used for the display ofthe item text, and hence the item text corresponding to the full-namecode includes Chinese characters for Japanese (i.e., Kanji) and numbersand/or figures so that it can be displayed as recorded. (It is notedthat, in the Japanese patent application corresponding to thisapplication, the text includes words and/or phrases of Japanese Kanjicharacters (Chinese characters) normally used in Japan. Therefore, thefull-name code corresponds to the text written by the charactersincluding the Kanji characters so that they can be displayed as theyare.) Contrary, the sorting code is a code used in the search operationutilizing the item text, and the item text corresponding to the sortingcodes does not include Kanji characters. Namely, the sorting codecorresponds to the text written in the form of the reading sound(pronunciation) of the words so that the search operation describedlater can be performed using the sorting code.

Next, out of the application items, the description will be speciallygiven to the genre. In the examples of FIGS. 7A to 7C, the applicationitems of the video genre, the music/karaoke genre and the sub genre aredefined in the class "GENRE". The description of the item textcorresponding to the application items in the class "GENRE" may bebasically freely determined by the author or the like, similarly to thecase of other application items. However, if the description of the itemtext corresponding to those application items is completely free andunlimited, it may be difficult to make the search operation using theapplication description code. For this reason, in view of the searchoperation, there is a method in which the description (i.e., contents)of the item text corresponding to the genre is slightly limited. One oftwo following methods may be employed to limit the description of theitem text in this view.

The first method is to limit the contents of the item text correspondingto the application description code of "GENRE" to only somepredetermined contents and obliges the author to select the contentsfrom those predetermined ones when determining the item text. By this,the contents of the item texts corresponding to the application items of"GENRE" are regulated and the search operation using the item text canbe advantageously performed.

The second method is to limit the manner of describing the description(contents) of the item text to a predefined style of "Mark+Characters".In this case, an item text pointer (described later in detail) pointsthe head address of the "Characters" part of the item text thus defined.As the "Mark" part, figures of a limited byte number may be used. Withthis treatment, the search operation can be carried out using the "Mark"parts of the item texts, thereby facilitating the search operation. Inaddition, since the pointer of the item text is directed to the head ofthe "Character" part, only the "Character" part of the item text isdisplayed and the "Mark" portion of the text is not displayed. Usingthis method, since the "Mark" part exists as a hidden information, itmay be used by only some special kind of DVD players. As describedabove, by applying the limitation or rule to the description of the itemtext corresponding to the "GENRE", the search operation may be moreeffective.

FIG. 8 shows an example of the above described second method using the"Mark+Character" style item text description. In this case, the itemtexts corresponding to the sorting codes in the class "GENRE" is of astyle:

(Text code)+(Space code)+(Text data) The text data describes the readingsound (character without Kanji (Chinese characters)) of the contentscorresponding to the "text code" or the detail thereof, and are used forthe search operation by a general player. The text code is used for thesearch operation by the players of special types. It is also possible todescribe the item text corresponding to the full-name code in the samestyle and to use the text code in them for the search operation and thetext data for the display. In that case, the item text of the sortingmay be omitted. The search operation will be described later in moredetail.

Next, the recording manner of the text information on the DVD 1 will bedescribed. FIG. 9 shows the recording format of the text information.The text information 121 is recorded within the video manager 2 shown inFIG. 1. The text information 121 includes a text information manager122, one or more language unit pointers 123 and one or more languageunits 124. The text information manager 122 includes an end position(address) of the text information manger 122 itself, and a number of thelanguage units 124 under the management by the text information manager122. The language unit 124 is a unit of text information described inone language. Namely, the number of the language units 124 correspondsto the number of the languages by which the text information is preparedand recorded. For example, if the text information is prepared by fourlanguages, English, German, French and Japanese, the number of thelanguage units 124 is four. The language unit pointer 123 is providedfor each language unit 124, and includes information as to the languageof the text included in that language unit 124. The language unitpointer 123 also includes information relating to the character codesystem (JIS, ISO, etc.) used in the description of the text in thelanguage unit 124, and the recording address of the correspondinglanguage unit 124 within the text information 121.

The language unit 124 includes a language unit information 125, aplurality of text pointers 126 and a text data 127. The language unitinformation 125 includes information relating to the contents of thelanguage unit 124, e.g., an end address of the language unit 125 itself.The text pointer 126 indicates the recording position of an item textpointer 129 which is described with respect to the volume and the title.

The text data 127 includes a text information 128, a plurality of itemtext pointers 129 and an item text area 130. The text information 128includes information relating to the text data 127, specificallyinformation 128a (=m) of the number of item codes 129a in the text data127. The item texts #1 to #n are comprised of data expressing the text,described with respect to the hierarchical layers or application items,in the form of a predetermined character code. By way of example, whenthe characters of "Gone With The Wind" is recorded as the productionname of a movie, the character code sequence corresponding to thecharacters is recorded as the item text. The character sequence recordedas the item text is of variable length, and is recorded successivelywithin the item text area 130 with a delimiter added at its end.

The item pointer 129 includes the item code 129a and a text head pointer129b. The item code 129a indicates, as described above, the layer towhich the item text corresponding to the item text pointer 129 belongs(in the case of hierarchy description code) or the contents of thecorresponding item text (in the case of application description code).The text head pointer 129b represents the recording address, within theitem text area 130, of the item text corresponding to the item textpointer 129 to which it belongs. As described above, the plural itemtexts #1 to #n are recorded successively within the item text area 130,and hence the respective item texts #1 to #n are specified bydesignating the recording address in the item text area 130 using thetext head pointer 129b. If there exists an item text described incorrespondence with the item text code, the item text pointer and theitem text may be basically provided in one-to-one correspondence.Alternatively, if an identical item text is commonly and repeatedly usedfor plural item text pointers, a unique item text may be described inthe item text area 130 and the plural item text pointers may bedetermined to designate the recording position of the unique item text.By this, the recording area in the item text area 130 may be efficientlyused. The selection of the method of describing the item text in theitem text area 130 is entrusted to the author who produces the text. Asdescribed later, there are item codes which have no corresponding itemtext, and therefore the numbers m and n are not always equal to eachother.

The first item text pointer #1 specifies the item text which has theitem code 129a indicating the hierarchical code indicative of the volumewithin the hierarchical structure, and the item text pointers #2, #3, .. . specifying the item texts relating to the volume follows the firstitem text pointer #1. Then, the item text pointer specifying the itemtext which has the item code 129a indicating the first title isrecorded, and the item text pointers specifying the item texts relatingto the first title follow. Then, the item text pointer specifying theitem text which has the item code 129a indicating the second title isrecorded, and the item text pointers specifying the item texts relatingto the second title follow. Thereafter, the item codes 129a and the itemtext pointers are described for all existing titles in the same manner.By describing the item text pointers 129 in a grouped manner toconstitute a group for each volume and/or title, it becomes easy tosearch for the item text on the volume and/or the title basis using thetext pointer 126. The item text pointer 129 is always and necessarilydescribed for the volume and titles. However, with respect to the itemtext pointers 129 which do not have corresponding item text, the texthead pointer 129b in the item text pointer 129 is set to "0" asdescribed later.

The text pointer 126 indicates the recording address, within the textdata 127, of the item text pointer 129 corresponding to the volume andtitle. Namely, the volume address 126a, which is the contents of thetext pointer #1, indicates the recording address, within the text data127, of the item text pointer 129 having the item code 129a indicatingthe hierarchical layer "volume". The title addresses 126b, which are thecontents of the text pointers #2 to #100, indicate the recordingaddress, within the text data 127, of the item text pointers 129 havingthe item codes 129a indicating the hierarchical layer "title". If thereis no corresponding title, the title address 126b is set to "0".

Next, the relationship between the item code and the item text will bedescribed with reference to the description examples. FIG. 10 shows anexample of description of item codes, and FIG. 11 shows the hierarchicalstructure corresponding to the example of FIG. 10. It is noted that FIG.10 shows the relationship of the contents of the item code, the itemcode and the contents of the item text for the purpose of explanation.In practice, the item code 129a is recorded at the position shown inFIG. 9 as the hexadecimal code, and the item text is recorded in theitem text area 130 in FIG. 9 as sequence of character codes. Inaddition, the address indicating the recording position of the item textin the item text area 130 is recorded, in pair with the item code, inthe item text pointer 129 as the text head pointer 129b. This is asdescribed above.

By referring to FIG. 10, first, the item code "0" indicating the volumeis described. Although the contents of the text in FIG. 10 is"<OPTION>", this means that certain characters may be described as theitem text, and does not means that the word "<OPTION>" is described. Themeaning of the <OPTION> is the same for the title and the PTT. If theitem code is the application description code, the item textcorresponding to the application item is basically always described. Onthe contrary, if the item code is the hierarchy description code, itmerely represents the presence of the hierarchical layer indicated bythe code and hence it is not necessary to describe the correspondingitem text if the author does not think it necessary. If nothing isdescribed in the corresponding item text in this way, "0" is describedat the text head pointer 129b in the item text pointer 129.

Subsequently, the hierarchical code "1" indicating the title isdescribed, and further there are described the application descriptioncodes indicating the production name, the director and the main actor,and the corresponding item texts. Since these item texts are recorded inpair with the hierarchy description code indicating the title (2ndline), it can be easily recognized that these item texts are describedin relation with the title. Thereafter, since there are recorded thehierarchy description codes indicating PTT, it is recognized thatanother layer "PTT" exists under the layer "title" and that the itemtext corresponding to the application description codes of scene name(8th line) is described in relation with this PTT. In this example,there further exist two PTTs (9th line and 10th lines), and the itemtext with respect to the third PTT (10th line) is described incorrespondence with the application description code of scene name. Thehierarchical structure described by the example of FIG. 10 is shown inFIG. 11.

In the example of FIG. 10, only the full-name codes (see FIGS. 7A to 7C)are shown with respect to the application description codes. However, inpractice, the sorting codes for the same application items may bedescribed just after the full-name codes in the item code 129a (FIG. 9).For the sorting code, the characters (including no Chinese characters)are described as the corresponding item text in the item text area 130.Such text is described for the purpose of the search operation using thetext information. Also in the following description examples in FIGS. 12and 14, the illustration of the sorting codes of the application codesis omitted in the same manner. In addition, the line numbers in FIGS.10, 12 and 14 are applied for the sake of explanation only, and are notcoincident with the lines at which those texts are actually described inthe item text area 130. This is same in the following FIGS. 12 and 14.

There are two rules for the describing manner of the item codes. Thefirst rule is as follows:

A hierarchy description code can be omitted if all of the followingconditions are satisfied:

(a) With respect to a hierarchical layer, there is no hierarchydescription code branched from the identical higher layer.

(b) There is no item text in relation with the hierarchy descriptionlayer.

(c) There is no item text corresponding to the application item for theinformation unit which is related to the hierarchy description code.

For example, in the example of FIG. 10, there is only one parental-IDand there is no item text for the layer "parental-ID", the hierarchydescription code of the parental-ID is omitted (refer to FIG. 10 andFIG. 5 for comparison). In addition to the first rule, even if there isother layer on the same hierarchical level branched from the higherlayer, the hierarchy description code can be omitted if there is no itemtext in its own layer and in the layers at the same and lowerhierarchical levels. This is why there is no description for the layerslower than the cell in FIG. 10.

The second rule is as follows:

All the hierarchy description codes for the information units must bedescribed if all of the following conditions are satisfied:

(a) For a certain layer, there are plural information units which havethe same higher layer at the layer of one level higher.

(b) At least one item text is described at any layers which are existingunder the information units.

This is because, it is necessary to describe the hierarchy descriptioncode so as to indicate the presence of the information units at thelayer even if the item texts do not exist in the respective layers. Inaddition, in each layer, the number of the information unit on the samehierarchical layer corresponds to the description order of the hierarchydescription codes. Therefore, in the example of FIG. 10, although thethere is not prepared an item text of the scene name of the second PTT(9th line), this hierarchy description code (i.e., "PTT" at 9th line)must be described, because, if this is omitted, the number of the PTTcan not be recognized and the PTT #3 is erroneously regarded as PTT #2in the case of FIG. 10. It is noted that the hierarchy description codesare always and necessarily described for the volume and the title.

FIG. 12 shows another example of the description of the item codes andthe item texts. This example is directed to the case where audioinformation is recorded on the DVD. Since the data capacity of th audioinformation is generally much smaller than that of the videoinformation, data of the plural CDs may be recorded on a single DVD. Inthe example of FIG. 12, one title corresponds to one album (i.e., oneCD), and one PTT corresponds to one song. The hierarchical structure ofthis example is shown in FIG. 13.

Further, FIG. 14 shows still another example of the description of theitem codes and the item texts. This example is directed to the karaokesong collection, and the hierarchical structure thereof is shown in FIG.15. In this example, one title corresponds to one song, and there arerecorded a song by a male singer and a song for duet. As the item textof the audio channel, the name of the vocalist for the vocal partrecorded in the channel is described. Accordingly, for example, if thefifth channel (channel #5 in FIG. 15, lines 27 and 28) in the title #2is selected, the user can enjoy the singing with Ootuki Miyako (Japanesefemale singer). Also in this example, the introduction part of thelyrics of the songs are described in the layer of PTT and cell (see.lines 30-31, 33-34).

As described above, according to the present invention, the item code,comprised of one of the hierarchy description code and the applicationdescription code, is recorded in pair with the item text, and furtherthe hierarchy description codes of other hierarchical layers (levels)are described to identify the position of the corresponding informationunits within the hierarchical structure. Therefore, it is possible torecognize as to which information in which layer, within thehierarchical structure, the item text corresponds to and what is thecontents of the item text. This enables recording the text informationfor arbitrary hierarchical layer so as to clarify the correspondencebetween the text information record and the information unit relating tothe text information. In addition, since it is necessary to record thehierarchy description code which indicates the hierarchical layer and towhich there exist corresponding texts, the recording capacity may beeffectively used.

If there are plural information units on the same layer and only some ofthe information units from the beginning have the text information onthe layers and on their lower layers, the hierarchy description codesmay be omitted for the subsequent information units. This is because,since the number of the information unit corresponds to the descriptionorder of the hierarchy description code, the corresponding informationunit can be identified even if the hierarchy description codes areomitted for those information unit.

Next, the description will be given of the method of defining uniquecodes as the application description codes. It has been described thatthe unique cods may be defined as the unique codes. The unique codes maybe advantageously used for the search operation in which the recordedinformation is searched for using the text information. Namely, bydescribing a class or the like used for the search operation as theunique codes, the search operation can be smoothly performed. FIGS. 16Ato 16C shown an example in which the classes used for the searchoperation are defined using the unique codes. In FIG. 16C, theclassification by the first one Japanese letter is made for the names ofthe artists (singers), and the classes are defined using the uniquecodes. Specifically, ten unique codes corresponding to Japanese lettercolumns are provided. Here, the artist name is classified by their firstJapanese letter. For example, the first Japanese letter of the artistname "HORIUCHI TAKAO" is "HO", and hence this name belongs to theJapanese letter column " (HA)", i.e., the full-name code 234 and thesorting code 235 (Japanese letter column " (HA)" includes five Japaneseletters, " (HA)", " (HI)", " (HU)", " (HE)", " (HO)"). In addition, itis ruled that the item texts for the item codes thus defined aredescribed in the style shown in FIG. 17, i.e., (SINGER NAME)₋₋ (SONGNAME)₋₋ (TITLE No.). By describing the item text using the unique codes,the reproducing apparatus can pick up the item texts corresponding toeach unique code and product a search table as shown in FIG. 17, therebyenabling the rapid search and display of the search result. For example,in order to enable the search within the range of volume, the item codesof the unique codes are described together at the layer of the volume.Further, the combination of the item codes and the item texts as shownin FIG. 17 may be recorded on the other area which is used by thereproducing apparatus of some special types.

If the search for the singer whose name begins with Japanese letter "(A)", is made without the above description using the unique codes, thereproducing apparatus first searches for the item code "101" forsorting, corresponding to " (A)", makes the list including the itemtexts which have the Japanese letter " (A)" at the first letter from theitem texts corresponding to the sorting code "101", and then displaysthe result. Therefore, in order to search for the character in the itemtexts, the search must be made in the item text area 130 every time byreferring to the item text pointer 129, thereby requiring a longprocessing time. On the contrary, if the classes for the search isrecorded in advance using the unique codes, the search table like theone shown in FIG. 17 can be readily produced. Therefore, it isunnecessary to refer to the contents of the item texts every time thesearch is made, thereby enabling rapid search operation. The detaileddescription of the search operation will be described later.

(II) Embodiment of Recording Apparatus

Next, an embodiment of recording apparatus for recording the abovementioned control information, video information and audio informationonto the DVD 1 will be explained with reference to FIG. 18.

At first, a construction and an operation of the recording apparatus asthe embodiment is explained with reference to FIG. 18.

As shown in FIG. 18, a recording apparatus S1 as the present embodimentis provided with: a VTR (Video Tape Recorder) 70; a memory 71; a signalprocess unit 71; a hard disk (HD) device 73; a hard disk (HD) device 74;a controller 75; a multiplexer 76; a modulator 77; and a masteringdevice 78.

Nextly, an operation of the present embodiment is explained.

Record information R, which is a raw material such as audio information,video information etc. to be recorded on the DVD 1, is temporarilyrecorded in the VTR 70. Then, the record information R temporarilyrecord in the VTR 70 is outputted to the signal process unit 72 by arequest from the signal process unit 72.

The signal process unit 72 applies an A/D (Analog to Digital) convertingprocess and a signal compressing process to the record information Routputted from the VTR 70, and time-axis-multiplexes the audioinformation and the video information to output it as a compressedmultiplexed signal Sr. After that, the compressed multiplexed signal Sroutputted therefrom is temporarily stored into the hard disk device 73.

Along with this, the memory 71 classified the record information R intoa plurality of partial record information Pr in advance, and temporarilystores content information related to the partial record information Prwhich is inputted beforehand on the basis of a cue sheet ST, on whichcontrol information related to the respective partial record informationPr are written. Then, the memory 71 outputs it as a content informationsignal Si on the basis of a request from the signal process unit 72.Then, the signal process unit 72 generates and outputs an accessinformation signal Sac corresponding to the partial record informationPr with referring to a time code Tt, on the basis of the time code Ttcorresponding to the record information R outputted from the VTR 70 andthe content information signal Si outputted from the memory 71. Then,the access information signal Sac is temporarily stored in the hard diskdevice 74. The above described processes are performed with respect tothe whole record information R.

When the above described processes are finished as for the whole recordinformation R, the controller 75 reads out the compressed multiplexedsignal Sr from the hard disk device 73, reads out the access informationsignal Sac from the hard disk device 74, generates additionalinformation DA on the basis of these read out signals, and stores theadditional information DA into the hard disk device 74.

The concrete contents of the text information 121 is determined by theauthor and/or the producer. This is carried out in the following manner.First, the author determines the contents of the text information to berecorded and the correspondences between the text information and theitem codes. Then, the author successively describes the text informationin the item text area 130 as the item texts, and records the recordingaddresses of the text information, as the text head pointer 129b,together with the item codes. Thereby, item texts and plural item textpointers 129 are produced. Thereafter, the author produces the textinformation 128, the text pointers 126, the language unit information125 and so on the basis of the item texts and the item text pointers 129thus produced, thereby completing the production of the language units124. The above process is performed for each language independently.Finally, the language unit pointers 123 for plural language units 123and the text information manager 122 are produced. By this, theproduction of the text information 121 is completed.

The text information 121 thus produced is temporarily sorted in the harddisk device 74, and then included in the additional information DA bythe control of the signal processing unit 72. Namely, the textinformation is included in the additional information DA as theinformation to be recorded in the video manager 2. On the other hand,the controller 75 performs a time management for each of the operationsof the signal process unit 72, the hard disk device 73 and the hard diskdevice 74, and reads out the additional information DA from the harddisk device 74, so that the controller 75 generates and outputs anadditional information signal Sa corresponding to the read outadditional information DA, and generates and outputs an informationselection signal SCC to time-axis-multiplex the compressed multiplexedsignal Sr and the additional information signal Sa.

After that, the compressed multiplexed signal Sr and the additionalinformation signal Sa are time-axis-multiplexed by the multiplexer 76 tobe outputted as an information added compressed multiplexed Sap. In theform of the information added compressed multiplexed information Sap,the information to be recorded is produced by multiplexing the controlinformation and the video and/or audio information according to theswitching control by the information selection signal Scc from thecontroller 75, and is of the physical structure (physical format) asshown in FIG. 1. If there exists the sub picture information to berecorded, it is inputted by other means such as a hard disk device notillustrated, to the signal process unit 72, so that it is processed inthe same manner as the video and audio information thereat.

Then, the modulator 77 adds an error correction code (ECC), such as aReed Solomon code, and applies a modulation such as an eight to sixteen(8-16) modulation with respect to the information added compressedmultiplexed signal Sap outputted from the multiplexer 76, and generatesand outputs a disk record signal Sm to the mastering device 78.

Finally, the mastering device 78 records the disk records signal Sm to astamper disk, which becomes a maser (i.e. a cutting dye) for theproduction of an optical disk. Then, by use of this stamper disk, anoptical disk as a replica disk, which can be on sale in the generalmarket, i.e. the DVD 1, can be produced by a replication device notillustrated.

In this manner, there is produced a DVD on which the text information121 having the structure shown in FIG. 9 is recorded in the videomanager 2.

(III) Embodiment of Reproducing Apparatus

Next, an embodiment of reproducing apparatus for reproducing theinformation recorded on the DVD 1 by the above mentioned recordingapparatus will be explained with reference to FIGS. 19 to 22.

At first, a construction and an operation of the reproducing apparatusas the embodiment is explained with reference to FIG. 19.

As shown in FIG. 19, a producing apparatus S2 as the present embodimentis provided with: an optical pickup 80; a demodulate and correct unit81; stream switches 82 and 84; a track buffer 83; a system buffer 85; ademultiplexer 86; a VBV (Video Buffer Verifier) buffer 87; a videodecoder 88; a sub picture buffer 89; a sub picture decoder 90; a mixer91; an audio buffer 92; an audio decoder 93; a PCI (Presentation ControlInformation) buffer 94; a PCI decoder 95; a high light buffer 96; a highlight decoder 97; an input unit 98; a display unit 99; a systemcontroller 100; a drive controller 101; a spindle motor 102; and aslider motor 103. The construction shown in FIG. 9 only illustrates theportions related to the video and audio reproduction of the reproducingapparatus S2. The description and the detailed explanation as for servocircuits to servo-control the optical pickup 80, the spindle motor 102,the slider motor 103 and the like are omitted since they are constructedin the same manner as the conventional arts.

Nextly, an overall operation of the present embodiment is explained.

The optical pickup 80 includes a laser diode, a polarization beamsplitter, an objective leans, a photo-detector and the like notillustrated, and irradiates a light beam B as a reproduction light withrespect to the DVD 1. The optical pickup 80 receives a reflection lightof the light beam B from the DVD 1, and outputs a detection signal Spcorresponding to information pits formed on the DVD 1. At this time, thetracking servo control and the focus servo control are operated withrespect to the objective lens etc. of the optical pickup 80 in the samemanner as the conventional art so that the light beam B can beirradiated precisely onto the information track of the DVD 1 and thelight beam B can be focused on the information record surface of the DVD1.

The detection signal Sp outputted from the optical pickup 80 is inputtedto the demodulate and correct unit 81, where a signal demodulationprocess and an error correct process are applied to it to generate ademodulation signal Sdm, which is outputted to the stream switch 82 andthe system buffer 85.

The opening and closing operation of the stream switch 82, to which thedemodulation signal Sdm is inputted, is controlled by a switch signalSsw1 from the drive controller 101. When it is closed, the stream switch82 passes therethrough the inputted demodulation signal Sdm as it is tothe track buffer 83. When it is opened, the demodulation signal Sdm isnot outputted therethrough, so that unnecessary or useless information(signal) is not inputted to the track buffer 83.

The track buffer 83, to which the demodulation signal Sdm is inputted,consists of a FIFO (First In First Out) memory, for example, The trackbuffer 83 temporarily stores the inputted demodulation signal Sdm, andcontinuously outputs the stored demodulation signal Sdm when the streamswitch 84 is closed. The track buffer 83 compensates a difference orfluctuation in the data amount between respective GOP under the MEPG 2method, and continuously outputs the demodulation signal Sdm, which isdiscontinuously inputted due to a track jump in the aforementionedseamless reproduction, in case of reading the data divided into theinterleaved units IU, so as to avoid the interruption of thereproduction due to the discontinuity.

The opening and closing operation of the stream switch 84, to which thedemodulation signal Sdm is continuously inputted, is controlled by aswitch signal Ssw2 from the system controller 100 such that the variousbuffers at its posterior stage may not be over-flown or, on thecontrary, may not become empty to stop the decoding process, in theseparating process by the demultiplexer 86.

On the other hand, the system buffer 85, to which the demodulationsignal Sdm is inputted in parallel with the track buffer 83, accumulatesthe video manager 2, the control data 11 of the VTS 3 and the like(refer to FIG. 1) which are detected firstly upon loading the DVD 1 andwhich are related to the whole information recorded on the DVD 1. Then,the system buffer 85 outputs the accumulated data as a controlinformation Sc to the system controller 100, and temporarily stores theDSI packet 51 for each navi-pack 41 (refer to FIG. 1) as the occasiondemands while reproducing the information, to output it also as thecontrol information Sc. The text information 121 included in the videomanager 2 is temporarily stored in th system buffer 85, and is suppliedto the system controller 100 as the control information Sc. The systemcontroller 100 stores these information in the RAM 100a.

The demultiplexer 86, to which the demodulation signal Sdm iscontinuously inputted through the stream switch 84, separates the videoinformation, the audio information, the sub picture information and thePCI packet 50 for each navi-pack 41 respectively from the inputteddemodulation signal Sdm, and outputs them as a video signal Sv, a subpicture signal Ssp, an audio signal Sad and a PCI signal Spcrespectively to the VBV buffer 87, the subs picture buffer 89, the audiobuffer 92 and the PCI buffer 94. There may be a case where, in thedemodulation signal Sdm, different streams of the audio information orthe sub picture information in a plurality of different languages areincluded as the audio or sub picture information. In that case, adesirable language is selected for the audio to sub picture informationby a stream selection signal Slc from the system controller 100, so thatthe audio to sub picture information in the desirable language isoutputted to the audio buffer 92 or the sub picture buffer 89.

The VBV buffer 87, to which the video signal Sv is inputted, consists ofa FIFO memory, for example. The VBV buffer 87 temporarily stores thevideo signal Sv and outputs it to the video codecoder 88. The VBV buffer87 compensates the difference or fluctuation in the data amount betweenrespective pictures of the video signal Sv compressed by the MPEG 2method. Then, the video signal Sv in which the differences in the dataamount are compensated, is outputted to the video decoder 88, and isdecoded by the MPEG 2 method to be outputted as a decoded video signalSvd to the mixer 91.

On the other hand, the sub picture buffer 89, to which the sub picturesignal Ssp is inputted, temporarily stores the inputted sub picturesignal Ssp, and outputs it to the sub picture decoder 90. The subpicture buffer 89 is to synchronize the sub picture information includedin the sub picture signal Ssp with the video information correspondingto the sub picture information, and to output it. Then, the sub picturesignal Ssp synchronized with the video information is inputted to thesub picture decoder 90 and is decoded to be outputted as a decoded subpicture signal Sspd to the mixer 91. In a case where the sub picturesignal Ssp includes video information to construct a frame, a selectionbutton etc. for displaying the menu picture plane, the sub picturedecoder 90 changes a display condition of the selection button etc. tobe displayed, in the sub picture signal Sspd on the basis of a highlight control information Sch from the system controller 100 to outputit.

The decoded video signal Svd outputted from the video decoder 88 and thedecoded sub picture signal Sspd outputted from the sub picture decoder90 (which is in synchronization with the corresponding decoded videosignal Svd) are mixed together by the mixer 91, and are outputted as afinal video signal Svp to be displayed to a display device such as a CRT(Cathode Ray Tube) device not illustrated.

The audio buffer 92, to which the audio signal Sad is inputted, consistsof a FIFO memory, for example. The audio buffer 92 temporarily storesthe audio signal Sad and outputs it to the audio decoder 93. The audiobuffer 92 is to synchronize the audio signal Sad with the video signalSv or the sub picture signal Ssp including the corresponding videoinformation, and delays the audio signal Sad in accordance with theoutput condition of the corresponding video information. Then, the audiosignal Sad, which is time-adjusted to synchronize with the correspondingvideo information, is outputted to the audio decoder 93. Then, apredetermined decoding process is applied thereat to the audio signalSad, and it is outputted as a decoded audio signal Sadd to a speakeretc. not illustrated. If it is detected by the system controller 100that it is necessary to temporarily stop (pause) the audio voice in thereproduction immediately after accessing, a pause signal Sca isoutputted from the system controller 100 to the audio decoder 93, sothat the output of the decoded audio signal Sadd is stopped temporarilyat the audio decoder 93.

The PCI buffer 94, to which the PCI signal Spc is inputted, consists ofa FIFO memory, for example. The PCI buffer 94 temporarily stores theinputted PCI signal Spc and outputs it to the PCI decoder 95. The PCIbuffer 94 is to synchronize the PCI packet 50, which is included in thePCI signal Spc, with the video information, the audio information andthe sub picture information corresponding to the PCI packet 50, andapply the PCI packet 50 to the video information and the like. Then,from the PCI signal Spc, which is synchronized with the correspondingthe video information and the like by the PCI buffer 94, a high lightinformation included in the PCI packet 50 is separated or extracted bythe PCI decoder 95, and is outputted as a high light signal Shi to thehigh light buffer 96. The portion of the PCI packet 50 other than thehigh light information is outputted as a PCI information signal Spci tothe system controller 100.

The high light buffer 96, to which the high light signal Shi isinputted, consists of a FIFO memory, for example. The high light buffer96 temporarily stores the inputted high light signal Shi and outputs itto the high light decoder 97. The high light buffer 96 is totime-compensate the high light signal Shi so as to precisely perform achange in the display condition of the selection item, which correspondsto the high light information, in correspondence with the sub picturesignal Ssp which includes the video information for the high lightinformation. Then, the time-compensated high light signal Shi is decodedby the high light decoder 97, and the information included in the highlight signal Shi is outputted as a decoded high light signal Shid to thesystem controller 100. Here, the system controller 100 outputs theaforementioned high light control signal Sch to change the displaycondition by the high light information, on the basis of the decodedhigh light signal Shid.

On the basis of the control information Sc inputted from the systembuffer 85, the PCI information signal Spci inputted from the PCI decoder95 and an input signal Sin inputted from the input unit 98 such as aremote controller, the system controller 100 outputs the aforementionedswitch signal Ssw2, the language selection signal Slc, the pause signalSca and the high light control signal Sch to correctly perform thereproduction corresponding to those input signals, and also outputs adisplay signal Sdp to display an operation condition etc. of thereproducing apparatus S2 to the display unit 99 such as the liquidcrystal device.

Further, the system controller 100 outputs a seamless control signalScs1 corresponding to the track jump process, to the drive controller101, when it detects by the control signal Sc etc. that it is necessaryto perform the track jump process such as a search in order to performthe seamless reproduction. Then, the drive controller 101, to which theseamless control signal Scsl is imputted, outputs a drive signal Sd tothe spindle motor 102 or the slider motor 103. By this drive signal Sd,the spindle motor 102 or the slider motor 103 moves the optical pickup80 such that the record position to be reproduced on the DVD 1 isirradiated with the light beam B (refer to an arrow of a broken line inFIG. 9), and the spindle motor 102 CLV-controls (Constant LinearVelocity-controls) the rotation number of the DVD 1. Along with this,the drive controller 101 outputs the aforementioned switch signal Ssw1on the basis of the seamless control signal Scsl, so as to open thestream switch 82 when the demodulation signal Sdm is not outputted fromthe demodulate and correct unit 81 while the optical pickup 80 is beingmoved, and so as to close the stream switch 82 when the demodulationsignal Sdm is started to be outputted, so that the demodulation signalSdm is outputted to the track buffer 83.

Next, out of the operations of the reproducing apparatus S2, thedescription will be given of the search and reproduction operationsusing the text information. In the reproducing apparatus S2 according tothe present invention, it is possible to search for the recorded videoand/or audio information using the text information recorded. The searchand reproduction operations using the text information will be describedbelow.

FIGS. 20 and 21 are the flowcharts showing the search operations usingthe text information. Now, it is assumed that the text information 121is described as shown in FIG. 14, and a user searches for and reproducesthe song "DREAMY ROUNDABOUT" sung by the artist (singer) "HORIUCHITAKAO" (see. 7th and 8th lines in FIG. 14). First, the user instructs,via the input unit 98, to make the search for the song using the name ofthe artist (step S1), and then designates the name of the artist"HORIUCHI TAKAO" (step S2). In this case, the name of the artist may beinputted by the user via the keyboard or the like, and alternatively maybe designated by selecting the candidates of the artists to be selectedwhich are displayed on the monitor in the order of the beginning letteror the like. When the name of the artist is designated, the systemcontroller 100 accesses to the text information 121 stored in theinternal RAM 100a to find out all item text pointers 129 which includeitem codes corresponding to the name of the artist (step S3).Specifically, the system controller 100 picks up all the item textpointers 129 which item codes 129a (sorting code) are "101", indicatingthe artist's name (see FIG. 7A).

Next, the system controller 100 refers to the text head pointer 129b forall item text pointers 129 thus found so as to read the correspondingitem texts, and finds out all the text pointers 129 corresponding to theitem texts in which the name "HORIUCHI TAKAO" is described (step S4).Then, the system controller 100 refers to the item texts thus found andalso to the other item texts corresponding to the same hierarchydescription code, and obtains the song names and the hierarchical layers(step S5). In this example, since the item text pointer 129corresponding to the 8th line of FIG. 14 is found in step S4, the systemcontroller 100 reads the item texts corresponding to the item textpointers around it (6th, 7th lines), and recognizes that the song nameis "DREAMY ROUNDABOUT" and that the song is on the layer of "title"because there is no description of PTT between the description of thetitle and the subject (song name) (i.e., there is no line between 7thand 8th lines). Further, the system controller 100 recognizes the numberof the title of that song counted from the first title by searching theitem text pointers 129 corresponding to the title from the head of theitem text pointer 129. It is noted that, as for the title, the number ofthe title can also be recognized by referring to the address of thecorresponding item text pointers 129 by using the title address 196b inthe text pointer 126. If plural PTTs are included in the title, thedescriptions of those PTTs can be obtained by the search, and hence theposition of the song thus found within the hierarchical structure can becorrectly recognized in any cases. When the hierarchical layers and thenumbers and the names of the songs which artist is "HORIUCHI TAKAO"recognized in this way, the system controller 100 displays all of thesong names on the display 99 (step S6). The user selects the song"DREAMY ROUNDABOUT", which he was looking for, from the list of thesongs on the display 99 (step S7. When the user selects the song, thesystem controller 100 searches for the audio information of the song onthe basis of the information relating to the hierarchy of the audioinformation, such as the title, PTT, etc., corresponding to the song(step S8).

FIG. 21 shows the method of the search performed in step S8. First, thesystem controller 100 makes the title search based on the titleobtained. Concretely, the system controller 100 refers to the titlesearch pointer table provided in the video manager 2 to acquire therecording position (recording address) of the VTS corresponding to thetitle (step S10). The title search pointer table is a table whichrepresents the relationship between the titles and the recordingpositions on the DVD of the VTS corresponding to the titles. Then, thesystem controller 100 searches for the VTS on the basis of the addressthus obtained (step S11). When the search of the corresponding VTS isfinished, the system controller 100 makes the PTT search on the basis ofthe information of PTT previously obtained (step S12). Concretely, thesystem controller 100 refers to the PTT search pointer table recorded inthe VTS, and obtains the PTT search pointer which indicates therecording address of the PGC corresponding to the PTT thus obtained. Inthis example, since the title is searched for, the search pointer of thePTT at the head of the title is obtained. Then, the system controller100 obtains the PGC corresponding to the song "DREAMY ROUNDABOUT" on thebasis of the search pointer thus obtained, and returns to the mainroutine of FIG. 20. Thereafter, the system controller 100 reproduces thedesignated song on the basis of the PGCI thus obtained (step S9). Inthis way, the search operation using the text information is performed.

As described above, according to the present invention, necessaryminimum hierarchy description codes are described, and text informationis recorded in pair with the information indicating the layer of thecorresponding information unit, and further the other information arealso recorded so as to identify the recording position in thehierarchical layers. Therefore, the hierarchical layer of theinformation unit and its number in the layer can be recognized, therebyenabling the search operation using the text information easily.

In the above example, the application item "artist" is used for thesearch operation. However, any other application items such as the nameof the composer, the main actress and the like may be used for thesearch operation in the same manner.

Next, the description will be given of the example in which the searchoperation is performed using the unique codes defined within theapplication description codes. Now, it is assumed that the unique codesare defined within the application description codes as shown in FIG.16C, and that the item texts corresponding to those unique codes aredescribed in the style shown in FIG. 17. In this case, the reproducingapparatus S2 produces the search table, as shown in FIG. 17, using theunique codes from the text information recorded on the DVD, and storesit in the memory of the like, e.g., in the RAM 100a. Namely, thereproducing apparatus S2 prepares the list in which item textscorresponding to the full-name codes 224 to 242 are arranged in theorder of the Japanese letter (from the first column starting " (A)" tothe last column " (WA)"). When the user searches for the song "DREAMYROUNDABOUT" by the singer "HORIUCHI TAKAO", he designates the searchusing the unique code (step S21), and then designates Japanese lettercolumn to which the beginning letter "HO" of the artist's name,"HORIUCHI" belongs (step S22). Then, the system controller 100 refers tothe search table shown in FIG. 17, finds out the item codescorresponding to the Japanese letter column of "HA" which item code is"234", and displays the corresponding item texts on the display 99 (stepS23). In this case, however, the title numbers at the end of the itemtext (see FIG. 17) are not displayed. The list displayed includes thepairs of the name of the artist and the song name as shown in FIG. 17,and the user sees them and selects the pair of "HORIUCHI TAKAO" and"DREAMY ROUNDABOUT" (step S24). After the designation by the user, thesystem controller 100 obtains the title number described at the end ofthe item text (see FIG. 17), and makes the search to reproduce the song(steps S25 and S26). The operations in steps S25 and S26 are the same asthe operation in steps S8 and S9 in FIG. 20.

By making the search using the unique codes as described above, thesystem controller 100 does not have to read the contents of the itemtexts and can obtain the object of the search immediately, therebyenabling the rapid search. Although the unique codes are defined for theJapanese beginning letter the artists in the above example, otherapplication items such as the names of songs, movies or English beggingletters can be defined as the unique codes to enable the search usingthose application items. By way of example, in the case of Englishbeginning letter, the unique codes for the alphabet letters A to Z aredefined, and the item texts are described in the style: (artist name₋₋song name₋₋ title No.) as shown in FIG. 17. By designating the beginningalphabet letter of the artist, the search can be made in the samemanner. In this way, it is possible to achieve the quick search if theauthor of the DVD defines in advance the unique codes which the user mayuse in the search operation.

If the number of the application items used for the search, such as theartist's name and so on, is small, the item texts may be describeddirectly as shown in FIG. 17, without using the unique codes. In thatcase, it is preferred that the song names and/or the search targets aredescribed with inserting the ending code (the space code) after theartist's name in the item texts. By this, a general player can read outthe artist names only, and the players of special type can use the otherinformation. In this case also, the item codes and item texts may bedescribed in the normal describing rule, and alternatively the itemtexts may be described in a special areas.

Next, the description will be given of the search operation in the casewhere the item text of the genre is constituted by the combination ofthe text code and the text data as shown in FIG. 8. FIG. 23 showsexamples of the description of the full-name item texts for music andkaraoke genre. Similarly to the other item codes and item texts, theitem codes are described in the predetermined positions 129a in the itemtext pointer 129 according to the hierarchical structure, and the itemtexts are described at the positions in the item texts are 130 indicatedby the corresponding text head pointers 129b. In this case, the texthead pointers 129b indicate the head of the text data after the textcodes (3 digits figure) and the space code. The contents of the textdata is freely determined dependently upon the author, and is read outand displayed as the text information of the music/karaoke genrecorresponding to a certain information unit in accordance with the texthead pointer 129b. The text code at the head portion of each item textis the 3 digits figure of fixed length prescribed in accordance with theclassification in FIG. 8, and the special DVD player in conformity withthe search operation using the text code knows the correspondences shownin FIG. 8. Therefore, when a song is searched for by designating a genrename, the DVD player displays the genre names corresponding to the textcodes to invite the user's selection, searches for the text codes fromthe item text area 130, instead of searching for the designated genrename, thereby easily acquire the information related to the target song(e.g., song name, singer name, heirarchical layer as the order in thelayer, etc.). The display for inviting the user's selection may be thedisplay of the genre and the text codes, instead of the genre name onlyas described above, so as to allow the user to designate it by directlyinputting the text code. Alternatively, the correspondence table in FIG.8 may be printed on the jacket of the DVD or the like so as to allow theuser to make the designation by referring to the jacket on which thetable is printed. The method of designating and reproducing the songafter acquiring the information related to the song is the same as thecase of other examples.

As described above, by constituting the item text by the combination ofthe text code and the text data like the manner shown in FIG. 8, theitem text to be displayed and the text code used for the searchoperation can be separated. Therefore, the text to be displayed can befreely determined while the speed of the search operation can beimproved.

In the above described embodiments, the text information describes thehierarchical structure lower than the volume layer. However, the layershigher than the volume layer, such as the disc set, disc, disc side mayalso be described in the text information. In that case, as the methodof the description, the hierarchy description codes may be assigned toeach layer from the highest layer in the same manner as the embodimentdescribed above. Alternatively, the layers higher than the volume layermay be described using the unique codes. In the latter method, a generalplayer can use the layers equal to and lower than the volume layer, anda special player (such as a disc changer) can use the layers higher thanthe volume layer to make a search over the plural discs and/or discsides. Therefore, the function of the player may be enhanced whilemaintaining the compatability to the general DVD players.

What is claimed is:
 1. An information recording medium having amanagement information area and recording information area,the recordinginformation area including a plurality of record information piecesconstituting a hierarchical structure comprising a plurality ofhierarchical layers; the management information area including:a layerinformation piece for specifying one of the plurality of hierarchicallayers; a kind information piece for indicating a kind of informationrelating to one of the record information pieces; a text group includinga plurality of text information comprising a plurality of layer relatedtexts and a plurality of record information related texts, at least oneof the plurality of layer related texts describing information relatedto the layer specified by the layer information piece, and at least oneof the plurality of record information related texts describinginformation related to the kind of information indicated by the kindinformation piece; and a text arrangement information piece, arranged inpair with one of the layer information piece and the kind informationpiece, indicating a position of a text information corresponding to thepaired one of the layer information piece and the kind informationpiece.
 2. The medium according to claim 1, wherein the layer informationpiece is arranged in an order in accordance with the hierarchicalstructure, and the kind information piece is arranged in pair with thelayer information piece specifying a hierarchical layer of the recordinformation piece corresponding to the kind information piece so as tospecify the position of the corresponding record information piecewithin the hierarchical structure.
 3. The medium according to claim 1,further comprising at least one specific layer information pieceindicating a recording position of the layer information piececorresponding to a specific layer out of the plurality of hierarchicallayers.
 4. The medium according to claim 1, further comprising anuppermost layer information piece indicating a recording position of thelayer information piece corresponding to the highest layer out of theplurality of hierarchical layers.
 5. The medium according to claim 1,wherein the record information pieces comprise video information, audioinformation, and sub-picture information recorded in a multiplexedmanner.
 6. An information reproducing apparatus for reproducinginformation from an information recording medium having a managementinformation area and recording information area,the recordinginformation area including a plurality of record information piecesconstituting a hierarchical structure comprising a plurality ofhierarchical layers; the management information area including:a layerinformation piece for specifying one of the plurality of hierarchicallayers; a kind information piece for indicating a kind of informationrelating to one of the record information pieces; a text group includinga plurality of text information comprising a plurality of layer relatedtexts and a plurality of record information related texts, at least oneof the plurality of layer related texts describing information relatedto the layer specified by the layer information piece, and at least oneof the plurality of record information related texts describinginformation related to the kind of information indicated by the kindinformation piece; a text arrangement piece, arranged in pair with oneof the layer information piece and the kind information piece,indicating a position of a text information corresponding to the pairedone of the layer information piece and the kind information piece, saidapparatus comprising:reading means for reading the information recordingmedium thereby obtaining a read signal; demodulating means fordemodulating the read signal thereby obtaining a demodulated signal;detecting means for detecting, from the demodulated signal, the textgroup; and displaying means for displaying information corresponding toat least a portion of the text information within the text group.
 7. Theapparatus according to claim 6, further comprising:selecting means forselecting information displayed by the displaying means; andreproduction control means for reproducing a record information piececorresponding to the information selected by the selecting means.
 8. Theapparatus according to claim 6, wherein the record information piececomprises video information, audio information and sub-pictureinformation recorded in a multiplexed manner, the apparatus furthercomprising:a video decoder for decoding the video information; an audiodecoder for decoding the audio information; and a sub-picture decoderfor decoding the sub-picture information.